Method for making automotive headliners

Abstract

Vehicle headliners are prepared with a core layer of a fiber-reinforced polyurethane foam. The polyurethane foam is prepared from a polyurethane-forming composition that uses water as a blowing agent and polyol or polyol mixture that has a high functionality and an average hydroxyl equivalent weight of 100-130. The selection of polyols permits cycle times to be reduced by allowing for faster demolding and shortened aging times before post-molding heat lamination steps can be performed.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims benefit of U.S. Provisional Patent Application 60 / 751,581, filed 19 Dec. 2005.BACKGROUND OF THE INVENTION

[0002] This invention relates to headliners for vehicles such as trucks and automobiles.

[0003] Headliners are used in the passenger compartments of various types of vehicles. They provide an aesthetically pleasing appearance, acoustical and vibrational damping, and in some cases incorporate energy-absorbing components intended to reduce risk of injury in a collision or other accident. The. headliner may also provide a certain amount of structural reinforcement to the vehicle. To achieve these things, the headliner in many cases includes a structural polymer foam component. Various types of headliner designs are described in U.S. Pat. Nos. 5,833,304, 6,204,209, 6,887,552 and 6,939,491, US Published Patent Applications No. 2004 / 0235376 and 2004 / 0235378, and WO publications 2001 / 54949, 2002 / 04252, 2002 / 42119 and...

Examples

example 1

[0070] A composite is prepared and molded in a modified aluminum mold to simulate vehicle headliner manufacturing conditions. The mold is an electrically heated aluminum mold equipped with an air bladder for sealing and degassing the tool. The internal dimensions of the mold are 20 inches×20 inches (51 cm×51 cm), with a depth of about 12-25 mm (½to 1 inch). An insert is placed in the mold to reduce the depth in some areas to 4-8 mm while leaving the depth in other areas at 10-16 mm.

[0071] A polyurethane composition is prepared from the following components:

TABLE 1ComponentParts by WeightPolyether Polyol A188.2Silicone Surfactant A22.0Gelling Catalyst A32.5Gelling Catalyst B41.0Gelling Catalyst C52.0Colorant0.5Water3.8Polymeric MDI6to 105 index

1A sucrose / glycerine-initiated poly(propylene oxide) having a hydroxyl equivalent weight of about 115 and a functionality of 4.1 hydroxyl groups / molecule, sold as Voranol 490 by Dow Chemical;

2An organosilicone surfactant sold as Tegostab ®B...

example 2

[0074] Example 1 is repeated, this time increasing the amount of water to 4.3 parts by weight and reducing the amount of polyol to 87.7 parts by weight. Demold time is again less than 60 seconds.

Comparative Sample A

[0075] Example 1 is again repeated, this time using a polyurethane-forming composition as follows. The polyols in this formulation have an average functionality of about 4.1 and an average hydroxyl equivalent weight of 137.

TABLE 2ComponentParts by WeightPolyether Polyol B178.65Polyether Polyol C210Silicone Surfactant B31.5Gelling Catalyst A41.5Gelling Catalyst B51.5Gelling Catalyst C61.8Gelling Catalyst D71.2Colorant0.45Water3.4Polymeric MDI8To 105 index

1A sucrose / glycerine-initiated poly(propylene oxide) having a hydroxyl equivalent weight of about 156 and a functionality of 4.1 hydroxyl groups / molecule, sold as Voranol 360 by Dow Chemical;

2An ethylene diamine-initiated polyol having a hydroxyl equivalent weight of 70 and a functionality of 4.0 hydroxyl groups / molec...

example 3

[0077] Comparative Sample A is repeated, except the polyurethane-forming composition is modified to contain 68.05 parts of Polyether Polyol B, 20 parts of Polyether Polyol C and 4 parts of water. The polyol mixture has an average functionality of about 4.1 and an average hydroxyl equivalent weight of 122. The demold time for this formulation is about 50 seconds.

[0078] This polyurethane-forming composition is then evaluated to make vehicle headliners on a production line. The tool in this case is a mold having a cavity that varies in thickness, so that the molded part has areas that are 6, 8 and 14 mm thick.

[0079] All components except the polyisocyanate are blended to form a formulated polyol component which is adjusted to about 25° C. The polyisocyanate is adjusted to about 27° C. The polyol component and polyisocyanate are mixed and sprayed onto a woven glass mat having a weight of about 105 g / m2 (0.34 ounces / square foot). Immediately after applying the polyurethane-forming comp...

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims benefit of U.S. Provisional Patent Application 60 / 751,581, filed 19 Dec. 2005.BACKGROUND OF THE INVENTION

[0002] This invention relates to headliners for vehicles such as trucks and automobiles.

[0003] Headliners are used in the passenger compartments of various types of vehicles. They provide an aesthetically pleasing appearance, acoustical and vibrational damping, and in some cases incorporate energy-absorbing components intended to reduce risk of injury in a collision or other accident. The. headliner may also provide a certain amount of structural reinforcement to the vehicle. To achieve these things, the headliner in many cases includes a structural polymer foam component. Various types of headliner designs are described in U.S. Pat. Nos. 5,833,304, 6,204,209, 6,887,552 and 6,939,491, US Published Patent Applications No. 2004 / 0235376 and 2004 / 0235378, and WO publications 2001 / 54949, 2002 / 04252, 2002 / 42119 and...

Examples

example 1

[0070] A composite is prepared and molded in a modified aluminum mold to simulate vehicle headliner manufacturing conditions. The mold is an electrically heated aluminum mold equipped with an air bladder for sealing and degassing the tool. The internal dimensions of the mold are 20 inches×20 inches (51 cm×51 cm), with a depth of about 12-25 mm (½to 1 inch). An insert is placed in the mold to reduce the depth in some areas to 4-8 mm while leaving the depth in other areas at 10-16 mm.

[0071] A polyurethane composition is prepared from the following components:

TABLE 1ComponentParts by WeightPolyether Polyol A188.2Silicone Surfactant A22.0Gelling Catalyst A32.5Gelling Catalyst B41.0Gelling Catalyst C52.0Colorant0.5Water3.8Polymeric MDI6to 105 index

1A sucrose / glycerine-initiated poly(propylene oxide) having a hydroxyl equivalent weight of about 115 and a functionality of 4.1 hydroxyl groups / molecule, sold as Voranol 490 by Dow Chemical;

2An organosilicone surfactant sold as Tegostab ®B...

example 2

[0074] Example 1 is repeated, this time increasing the amount of water to 4.3 parts by weight and reducing the amount of polyol to 87.7 parts by weight. Demold time is again less than 60 seconds.

Comparative Sample A

[0075] Example 1 is again repeated, this time using a polyurethane-forming composition as follows. The polyols in this formulation have an average functionality of about 4.1 and an average hydroxyl equivalent weight of 137.

TABLE 2ComponentParts by WeightPolyether Polyol B178.65Polyether Polyol C210Silicone Surfactant B31.5Gelling Catalyst A41.5Gelling Catalyst B51.5Gelling Catalyst C61.8Gelling Catalyst D71.2Colorant0.45Water3.4Polymeric MDI8To 105 index

1A sucrose / glycerine-initiated poly(propylene oxide) having a hydroxyl equivalent weight of about 156 and a functionality of 4.1 hydroxyl groups / molecule, sold as Voranol 360 by Dow Chemical;

2An ethylene diamine-initiated polyol having a hydroxyl equivalent weight of 70 and a functionality of 4.0 hydroxyl groups / molec...

example 3

[0077] Comparative Sample A is repeated, except the polyurethane-forming composition is modified to contain 68.05 parts of Polyether Polyol B, 20 parts of Polyether Polyol C and 4 parts of water. The polyol mixture has an average functionality of about 4.1 and an average hydroxyl equivalent weight of 122. The demold time for this formulation is about 50 seconds.

[0078] This polyurethane-forming composition is then evaluated to make vehicle headliners on a production line. The tool in this case is a mold having a cavity that varies in thickness, so that the molded part has areas that are 6, 8 and 14 mm thick.

[0079] All components except the polyisocyanate are blended to form a formulated polyol component which is adjusted to about 25° C. The polyisocyanate is adjusted to about 27° C. The polyol component and polyisocyanate are mixed and sprayed onto a woven glass mat having a weight of about 105 g / m2 (0.34 ounces / square foot). Immediately after applying the polyurethane-forming comp...